The Hitachi Fuel Injector Kit - 135917 is a comprehensive set of products designed for servicing a car's fuel injection system. It includes six different components, each specifically chosen to help improve the performance and efficiency of the fuel delivery process. The kit contains a fuel injector cleaner, a fuel system cleaner, a fuel filter, fuel line connectors, a fuel pressure regulator, and fuel injector seals. These products work together to remove build-up and deposits in the fuel system, improve fuel flow, and ensure proper fuel pressure for optimal engine performance. This kit is suitable for use on a variety of car models and can help extend the life of the fuel injection system while improving overall vehicle performance.